Along with rapid development of a Long Term Evolution LTE network throughout the world, the same operating company may usually provide coverage of multiple networks such as a 2nd-Generation 2G such as a Global System for Mobile Communication GSM network, a 3rd-Generation 3G network such as a Wideband Code Division Multiple Access WCDMA network, and an LTE network, etc. in many countries. Considering multiple aspects of cost, construction speed and the like, networks of operating companies in various countries cannot perfectly support Voice over LTE, VoLTE, at the present stage, and there is still a distance from quality of a voice call, particularly stability, compared with a conventional GSM network.
In addition, with development of an intelligent terminal, a more powerful Central Processing Unit CPU and a large screen consume a lot of standby time, which makes a problem about power consumption become an increasingly important consideration, and a dual-standby technology and the like may bring great power consumption.
At present, a terminal user usually manually selects a network, and such a selection manner is relatively more tedious. Moreover, the user can usually not select the most proper network due to lack of related technical knowledge. In addition, at present, selection of the user over a terminal network is usually selection over a network system (i.e. 2G, 3G, LTE, etc.), and the user may not be authorized by a terminal manufacturer to freely change a more detailed network parameter.